Using the name 'Monica' for a Muslim girl
8-4-2014 | IslamWeb
Question:
I have a question about naming people. This is the background name for Monica: Monica is an ancient name of North African origin (now Algeria) whose etymology is unknown. The earliest reference to the name is found in ancient Numidian inscriptions. The name might include a reference to the ancient Libyan god Mon. Saint Augustine's mother was named Monica, and she was born in Numidia, North Africa, although she also was a citizen of Carthage, hence the possibility it may be of Punic origin.[1] It has also been associated with the Greek word monos, meaning "alone".[2] Saint Monica's feast day is 27 August, and Monica is the patron saint of married women. it has various meanings and one of them is nun. Is it haram and shirk to use this name?
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad 
is His slave and Messenger.
said in Ahkaam Ahl Ath-Thimmah (The laws pertaining to non-Muslims living under Muslim protection):
"Names are of three kinds:
The first is exclusive to the Muslims. The second is exclusive to the non-Muslims. The third is common to both...... The second type: like Guirguis (George), Boutros (Peter), Youhanna (John), Matta (Matthew) and the like; they [the non-Muslims living under Muslim protection] are not prevented from such names, but it is not permissible for Muslims to be named with such names because it is imitating them in what is particular to them. The third type: Yahya, 'Eesa, Ayyoob, Dawood, Sulaymaan, Zayd, ‘Umar, ‘Abdullah, ‘Atiyyah, Mawhoob, Salaam, and the like; non-Muslims who are living safely in a Muslim land as well as the Muslims are not prevented from such names.”
Shaykh Bakr Abu Zayd mentioned in his theses about naming a new-born child different kinds of forbidden names; he said: “Naming with foreign names that are exclusive to the non-Muslims: A Muslim who is content with his religion stays away from them and does not hover around them. In our present time, there is a great affliction with them [such names]; a Muslim takes a name of a non-Muslim from Europe, America or elsewhere, and this is one of the worst kinds of sin and means of desertion (of religion), among which are: Boutros, Guirguis, George, Diana, Rose, Susan ... and other names which we have already mentioned above. This imitation of the non-Muslims by using their names, if it is done only out of following one’s desires or due to stupidity, then it is a great sin, and if one uses their names while believing that their names are better than Muslim names, then whoever does so is in great danger which shakes the foundation of his faith. In both cases, one should hasten to repent from it, and changing such names is a condition for repenting from them.”
Even though we are saying that using this name is forbidden, one does not commit Shirk merely by using it.
For more benefit, please refer to Fatwas 82724 and 87262.
Allaah Knows best.